Menstrual disturbances are very frequent in women with chronic renal insufficiency and they may be very severe. Nevertheless, there have been a paucity of studies investigating its pathophysiology and pathogenesis and the site of abnormality-hypothalamus, pituitary and/or ovary-remains unclear. Consequently, we propose to study a) basal LH, FSH, and prolactin secretion looking for abnormal cyclic and episodic secretion, b) the interaction of the sex steroids, estrogen and progesterone, on hormone release looking for abnormal inhibitory or facilitory effects, c) LH, FSH and prolactin responsivity to dopaminergic manipulation since dopamine is an important neurotransmitter in the regulation of the release of these hormones and d) the efficacy of long term treatment with the dopaminergic agonist bromocriptine in improving menstrual function, since this drug reverses the amenorrhea of hyperprolactinemia and hyperprolactinemia is very frequent in women with renal insufficiency. Correlation between degree of renal insufficiency and presence of hormonal disturbances will be attempted by studying women with mild, moderate or severe renal insufficiency, with the latter group being studied first. These results will be compared to those obtained from age matched women with normal menstural function.